The Banana Circle is a solution that integrates natural processes to treat and reuse waste, contributing to soil health and environmental sustainability. The system consists of a concave infiltration trench with a cylindrical shape, initially filled with a layer of gravel. Several layers of branches, leaves and natural debris are added to this layer, where facultative and anaerobic microorganisms act, responsible for stabilizing the organic matter. After this stage, the system has an artificial soil bed, intended for the treatment and final disposal of sewage. In this bed, the infiltration and evapotranspiration of the liquid part of the sewage occurs, the reuse of residual organic matter and the promotion of groundwater recharge. In some cases, this technique can be called a Fertility Center.

The biological filter is a system for filtering grey water, i.e. water from sink drains, showers and laundry tubs. This system consists of four filter boxes and a circle of banana trees. The first box consists of a common grease trap; the second is a box with gravel; the third is a box with sand and the fourth is a box with charcoal. In this way, the water that leaves homes returns to the environment with more than 70% purity, avoiding excess organic matter, soaps, grease and chemicals in community streams. The system filters the coarser material and grease and promotes the development of bacteria that decompose the particulate matter.

The TEVAP system, or Evapotranspiration Tank, is an innovative individual solution for the treatment and final disposal of effluents from domestic toilets. This system allows the proper disposal of human waste without causing water, soil or air pollution. Based on technical knowledge and practical experience, TEVAP uses easily obtainable materials, such as used tires, construction debris, bamboo and other locally available resources, and is designed to promote sustainable development, being environmentally correct, economically viable and socially fair.

Superadobe is an innovative bioconstruction technique that uses long fabric tubes or bags filled with compacted soil in layers to form robust and durable compression structures. The main raw material used is moist earth, which makes the construction process simple and affordable. This technology is particularly advantageous for the construction of toilets in hard-to-reach and isolated areas, providing a cost-effective solution for basic sanitation.

A biosystem is a facility that uses a biodigester to process organic waste, such as food scraps, animal manure and human feces, through an anaerobic process. This process transforms the waste into biogas and natural fertilizer. The biogas, which is filtered and stored in the equipment itself, can be used as cooking gas, providing up to 3 hours of gas per day. In addition to biogas, the system also generates a natural fertilizer, which is collected in a container located at the back of the equipment and can be used to fertilize crops.

The participatory governance process in the management of water bodies in a river basin involves several stages, including diagnosis, social mapping, agreement and planning. This process involves associations of residents and producers, the government in its various instances, the water and sewage concessionaire, and OTSS researchers. Together, they analyze the situation of the water bodies, identifying solutions for the rational use of water resources, the recovery of riparian forests, and the prevention and/or mitigation of disasters. These actions have a positive impact on the river basin and its use values, promoting sustainability and environmental resilience.

New construction of existing treatment, cleaning and sealing systems and installation of biodigesters, when necessary. As a complementary treatment, Root Zones are built - chambers filled with submerged filter media, where facultative and anaerobic microorganisms act, responsible for stabilizing the organic matter. To increase the efficiency of the system, macrophyte plants - species from marshes and humid environments - are used. The filtering material used is gravel 04, also known as “split stone”, at the bottom, and gravel 01 and gravel 00 at the top. Due to difficulties in the logistics of transporting the material, bamboo can be used as filtering material, since it is found in abundance locally.